1. Field of the Invention
Exemplary embodiments of the present invention relates to a secession alarm system of a smart key for a vehicle, and more particularly, to a system for alarming upon occurrence of secession of a smart key for a vehicle, in which wireless communication technology called near field communication (NEC) is applied to both a vehicle and a smart key such that a situation can be prevented in which a driver loses a smart key or does not carry it during the driving.
2. Description of Related Art
In recent years, along with generalization of a smart key system for a vehicle, a driver can open a vehicle door at the outside of a vehicle even without inserting a separate key into a door lock. Further, the driver can determine whether or not a smart key is placed inside the vehicle. If it is determined that the smart key is placed inside the vehicle, the driver can start the engine of the vehicle only by the manipulation of a start button switch of the smart key without any operation of the key into a key slot.
Such a function by the smart key is performed in such a manner that when the driver approaches the vehicle and operates a door opening/closing switch of the smart key, a door antenna mounted on a door handle senses the operation of the smart key to open the vehicle door.
In addition, when a driver carrying the smart key sits on a driver seat and operates the start button switch of the smart key, an indoor antenna senses the operation of the smart key that the driver carries to control the vehicle engine to be started up.
The smart key for vehicles is set to output an encrypted radio frequency signal so as to be operated in cooperation with the indoor antenna, and is configured to be operated only when there is a match between the encoded signals of the smart and the indoor antenna, which are transmitted and received wirelessly.
The demand for the smart key system for vehicles as described above is increased gradually due to convenience in opening/closing the door and starting up the engine, and a variety of products having similar functions to those of the smart key are put on the market.
However, for such a conventional smart key system for vehicles, there frequently occurs a problem involved in a typical driving habit of drivers.
That is, in the case where a vehicle driver requests his or her acquaintance to start up the engine while giving his or her smart key to the acquaintance in a parking lot or during the wintertime, the driver drives his or her started vehicle toward a destination inadvertently in a state where the acquaintance who have started up the engine does not return the driver the smart key unintentionally.
Like this, in the case where the driver drives the vehicle unintentionally in a state of not carrying the smart key, when he or she stops at a rest area for a short while, or parks or stops the vehicle at a place for some time on business on his or her way to the destination, a lock device does not work and the re-start of the engine is difficult if he or she stops the start of the engine, which makes it impossible to drive the vehicle again.
In this case, the driver cannot re-start the engine until the driver gets in touch with his or her acquaintance who carries the smart key unintentionally so that the acquaintance brings it to a place where the vehicle stops. Moreover, a problem may occur in that the vehicle must be towed inevitably in the worst situation.
Particularly, a designated-driver-for-hire service called “dae-ri-un-jeon” for when you've had too much to drink is recently becoming more common in Korea. When a vehicle driver calls for a rentable sober driver or a designated driver for hire, he or she will come to the vehicle driver's location and receive a smart key from the vehicle driver to drive the vehicle driver's home while carrying it. In this case, in the case where the rentable sober driver moves to a next place with him or her carrying the smart key unintentionally after the designated-driver-for-hire service has been complete, the smart key may be lost.
In addition, it is usual that a vehicle driver carries a smart key in his or her overcoat. Most drivers get on their vehicles and drive the vehicles after taking off their overcoats and placing them on a passenger seat or a rear seat. In this situation, the drivers often stop their vehicles for a short while on business with the engine being started. At this time, the drivers mostly get off their vehicles involuntarily in a state of not being aware of where the smart key is placed.
Like this, a vehicle driver gets off his or her vehicle for his or her business in a state of not being aware of the location of the smart key or thinking that he or she always carries it. Thus, a problem is caused in that the vehicle is left in a defenseless state with the engine being turned on for a given time period during the business.
That is, the conventional smart key system equipped in a vehicle encounters a problem in that if a smart key is positioned inside the vehicle, everyone can open the vehicle door and start the engine simply, and thus valuables in the vehicle may be stolen and even theft of a vehicle may occur.